Making 55 000 nanoscale images of Thomas Jefferson might sound like an eccentric art project, but this is the first demonstration of a new technique that harnesses the power of thousands of nanoscale pens working in synchrony.

Chad Mirkin and his colleagues at Northwestern University in Illinois, US, drew their Jeffersons using a microscopic pen that deposits dots of a molecular ‘ink’ onto a gold substrate in a controlled, aligned pattern. They have called the technique parallel dip-pen nanolithography (DPN).